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Med Chem Res (2012) 21:810–815
2-[(Z)-(5-Nitrofuran-2-yl)methylidene]-N,N-diprop-2-enyl-
hydrazine-1-carbothioamide (4g) Yield: 46.8%; mp:
exchangeable NH), Chemical Formula: C23H22N4O2S
Calculated for C, 66.01; H, 5.30; N, 13.39; Found: C,
70.32; H, 5.67; N, 11.20.
1
142–144°C; H-NMR (DMSO-d6) d (ppm): 3.69 (d, 4H,
C-1 methylene proton of allyl), 5.17 (dd, 2H, C-3 H cis of
allyl), 5.2 (dd, 2H, C-3 H trans of allyl), 5.86–5.88 (m, 2H,
C-2 H of allyl), 7.54–7.55 (m, 2H, aryl-H), 7.49 (s, 1H,
benzylidine H), 11.9 (s, 1H, D2O exchangeable NH);
Chemical Formula: C12H14N4O3S Calculated for C, 48.97;
H, 4.79; N, 19.04; Found: C, 48.96; H, 4.80; N, 19.10.
2-[(Z)-1-(4-Fluorophenyl)ethylidene]-N,N-diprop-2-enyl-
hydrazine-1-carbothioamide (4m) Yield: 34.0%; mp:
1
134–136°C; H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H,
methyl), 3.69 (d, 4H, C-1 methylene proton of allyl), 5.17
(dd, 2H, C-3 H cis of allyl), 5.2 (dd, 2H, C-3 H trans of
allyl), 5.86–5.88 (m, 2H, C-2 H of allyl), 7.71–7.73 (m, 4H,
aryl-H), 11.4 (s, 1H, D2O exchangeable NH); Chemical
Formula: C15H18FN3S Calculated for C, 61.83; H, 6.23; N,
14.42; Found: C, 61.84, H, 6.22, N, 14.40.
2-[(Z)-1-Phenylethylidene]-N,N-bis(phenylmethyl)hydrazine-
1-carbothioamide (5h) Yield: 46.5%; mp: 128–129°C;
1H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H, methyl), 4.76
(s, 4H, CH2 of benzyl), 7.25–7.26 (m, 10H, aryl-H),
7.72–7.73 (m, 5H, Ar–H), 10.4 (s, 1H, D2O exchangeable
NH); Chemical Formula: C23H23N3S Calculated for C,
73.96; H, 6.21; N, 11.25; Found: C, 70.32; H, 5.67; N,
11.20.
2-(Diphenylmethylidene)-N,N-bis(phenylmethyl)hydrazine-
1-carbothioamide (5n) Yield: 49.6%; mp: 164–165°C;
1H-NMR (DMSO-d6) d (ppm): 4.76 (s, 4H, CH2 of benzyl),
7.25–7.26 (m, 10H, aryl-H), 7.33–7.39 (m, 10H, Ar–H),
10.4 (s, 1H, D2O exchangeable NH), Chemical Formula:
C28H25N3S Calculated for C, 77.21; H, 5.79; N, 9.65;
Found: C, 77.22; H, 5.77; N, 9.70.
2-[(Z)-1-(2-Hydroxyphenyl)ethylidene]-N,N-diprop-2-enyl-
hydrazine-1-carbothioamide (4i) Yield: 65.2%; mp: 136–
137°C; 1H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H, methyl),
3.69 (d, 4H, C-1 methylene proton of allyl), 5.17 (dd, 2H,
C-3 H cis of allyl), 5.2 (dd, 2H, C-3 H trans of allyl),
5.86–5.88 (m, 2H, C-2 H of allyl), 7.71–7.73 (m, 4H, aryl-
H), 11.4 (s, 1H, OH), 11.9 (s, 1H, D2O exchangeable NH),
Chemical Formula: C15H19N3OS Calculated for C, 62.25; H,
6.62; N, 14.52; Found: C, 62.18; H, 6.63; N, 14.50.
2-[(Z)-1-Methylpropylidene]-N,N-diprop-2-enylhydrazine-
1-carbothioamide (4o) Yield: 46.1%; mp: 154–155°C; 1H-
NMR (DMSO-d6) d (ppm): 1.05 (t, 3H, CH3 of ethyl), 2.0 (s,
3H, methyl), 2.27 (q, 2H, CH2 of ethyl), 3.69 (d, 4H, C-1
methylene proton of allyl), 5.17 (dd, 2H, C-3 H cis of allyl),
5.2 (dd, 2H, C-3 H trans of allyl), 5.86–5.88 (m, 2H, C-2 H of
allyl), 8.57 (s, 1H, D2O exchangeable NH); Chemical For-
mula: C11H19N3S Calculated for C, 58.63; H, 8.50; N, 18.65;
Found: C, 58.60, H, 8.53, N, 18.68.
2-[(Z)-1-(4-Hydroxyphenyl)ethylidene]-N,N-bis(phenylmethyl)
hydrazine-1-carbothioamide (5j) Yield: 39%; mp: 221–
222°C; 1H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H,
methyl), 4.76 (s, 4H, CH2 of benzyl), 7.25–7.26 (m, 10H,
aryl-H), 7.72–7.73 (m, 4H, Ar–H), 10.4 (s, 1H, D2O
exchangeable NH), 11.2 (s, 1H, OH); Chemical Formula:
C23H23N3OS Calculated for C, 70.92; H, 5.95; N, 10.79;
Found: C, 70.32; H, 5.67; N, 11.20.
In vitro antimycobacterial activity
All compounds were screened for their in vitro antimyco-
bacterial activity against MTB, MDR-TB, and MC2 in Mid-
dlebrook 7H11 agar medium supplemented with OADC by
agar dilution method similar to that recommended by the
National Committee for Clinical Laboratory Standards for
the determination of MIC in triplicates. The MDR-TB clin-
ical isolate was obtained from Tuberculosis Research Cen-
ter, Chennai, India, and was resistant to isoniazid, rifampicin,
ethambutol and ofloxacin. The minimum inhibitory con-
centration (MIC) is defined as the minimum concentration of
compound required to give complete inhibition of bacterial
growth.
2-[(Z)-1-(4-Aminophenyl)ethylidene]-N,N-diprop-2-enyl-
hydrazine-1-carbothioamide (4k) Yield: 40.2%; mp:
[250°C; 1H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H,
methyl), 3.69 (d, 4H, C-1 methylene proton of allyl), 5.17
(dd, 2H, C-3 H cis of allyl), 5.2 (dd, 2H, C-3 H trans of allyl),
5.86–5.88 (m, 2H, C-2 H of allyl), 6.27 (s, 2H, amino),
7.71–7.73 (m, 4H, aryl-H), 11.4 (s, 1H, D2O exchangeable
NH); Chemical Formula: C15H20N4S Calculated for C,
62.47; H, 6.99; N, 19.43; Found: C, 62.46, H, 7.02, N, 19.40.
2-[(Z)-1-(4-Nitrophenyl)ethylidene]-N,N-bis(phenylmethyl)
hydrazine-1-carbothioamide (5l) Yield: 64.6%; mp: 138–
139°C; 1H-NMR (DMSO-d6) d (ppm): 2.13 (s, 3H,
methyl), 4.76 (s, 4H, CH2 of benzyl), 7.25–7.26 (m, 10H,
aryl-H), 7.72–7.73 (m, 4H, Ar–H), 10.4 (s, 1H, D2O
Cytotoxicity
Some compounds were further examined for toxicity
(IC50) in a mammalian Vero cell line at concentrations of
62.5 lg/ml. After 72 h of exposure, viability was assessed
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